Evacuator system and apparatus

ABSTRACT

A suction system, of the type employed in evacuating fluids from wounds or body cavities of medical patients, is provided with means for relieving suction pressure automatically in response to obstruction of the inlet to the system. The presence of an obstruction is detected in the form of an increase in vacuum pressure within the system which is sensed by a mechanical pressure transducer. The transducer in turn operates a switch which controls an electrically operated air valve adapted to introduce external or atmospheric air pressure into the system.

United States Patent Daniel A. Kadan 19 Split Tree Road, Soarsdale, N.Y.10583 21 Appl. No. 731,040

[22] Filed May 22, 1968 [45] Patented Feb. 23, 1971 [72] Inventor [54]EVACUATOR SYSTEM AND APPARATUS 10 Claims 3 Drawing Figs.

[52] U.S. (I 128/278 [51] Int. Cl A6lm l/00 [50] Field Search 128/278,276, 277, 172

[56] References Cited UNITED STATES PATENTS 2,351,828 6/1944 Marsh3,016,055 1/1962 Oldenburg 3,376,868 4/1968 Mondiadis PrimaryExaminerAdele M. Eager Attorney-Howard S. Reiter so ir-' [CONTROLAPPARATUS VACUUM 22 PRESSURE SOURCE V12 1 I EVACUATOR SYSTEM ANDAPPARATUS This invention pertains generally to the control of suctionapparatus, and more particularly, to the control of vacuum systems ofthe type which may be employed in evacuating fluids from wounds or bodycavities of medical patients.

Suction systems for evacuating fluids into a suitable receptacle areknown in the prior art. Such systems have been provided generally with areceptacle, such ,as as toppered jar, having an inlet and an outlet,together with a catheter device coupled to the receptacle inlet, and asource of vacuum or suction pressure coupled to the receptacle outlet.The catheter may be a hollow tubular element with inlet apertures formedalong the sides or at one end to admit fluids into the hollow interior.In use, the catheter is inserted into a cavity which requires fluiddrainage, and vacuum pressure is applied to form a vacuum within thereceptacle so as to draw fluids through the hollow catheter.

The practical application of these prior art systems has revealed thatfrequent cleaning of the catheterand catheter apertures is required toremove various small particles and tissue debris, which tend to blockthe passage of fluids to the receptacle. This procedure is undesirablegenerally, from the standpoint of its effect on a patients health, aswell'as from its requirement for personal attention by attendants whomight be occupied more gainfully with other tasks.

As an alternative to direct cleaning of the catheter itself, someattendants have been known to disconnect the vacuum source periodicallyfor short periods of time. This procedure is effective in .perrnittingdebris to fall away from the catheter inlets under the influence ofatmospheric pressure in the hollow interior. It suffers from recognizeddisadvantages, however, in that it continues to require personalattention by attendants, and such attention must be on a regularlyscheduled basis in order to be effective. A further disadvantage ofoperating on any regularly scheduled or simple periodic basis is thatinterruptions of suction may be made, frequently-, when they areentirely unnecessary due to absence ofobstructions at the catheter.,And, on the other hand, an obstruction may very well continue for aconsiderable and undesirable period of time before a scheduled cleaningor vacuum interruption is performed. I 1' It is the aim of thisinvention to providean evacuator system and control apparatus whichavoids these limitations and disadvantages of the prior art.

Accordingly, an object of this invention isthe' provision of anevacuator system of the type described,1with means for interruptingvacuumpressure in the receptacle, automatically, to clear obstructionsfrom the catheter inlet apertures.

A further object of this invention is the provision of means in anevacuator system of the typedescribed for interrupting vacuum pressurein the receptacle in response to blockage of catheter inlet apertures.

Still another object of this invention is 1to provide a selfclearingevacuator system which is simple and inexpensive to construct, is easyto maintain, and which requires a minimum number of moving parts andmotive power sources.

A feature of this invenn'on is the useof a pressure transducer whichoperates on electrical switchin response to detection of a selectedmaximum suction pressure within the receptacle of an evacuator system.The switchin turn operatesan electrically controlled vent-valve whichopens to vent the receptacle to atmospheric pressure and then closesagain. This cycle of opening and closing continues until'clearance ofthe catheter is signalled by the fact that suction pressure in thereceptacle remains below the selected maximum value.

These and other and further objects, ;features, and advantages of thisinvention are more clearly pointed out and distinctly claimed in thefollowing specification and claims and are fully illustrated in theaccompanying drawings, in which:

FIG. I is a diagrammatic representation of an evacuator systemconstructed in accordance with this invention;

FIG. 2 is a partial cross-sectional representation of a controlapparatus coupled together in accordance with this invention; and

FIG. 3 is a diagrammatic representation of an alternate embodiment ofthis invention.

Now, referring to the drawings more particularly, the evacuator systemillustrated in FIG. I may be seen to comprise a catch-bottle receptacle10, a source of vacuum pressure represented by black box 12 which iscoupled to receptacle 10 by lengths of vacuum conduit I4, 16, and anadjustable pressure-control apparatus represented by "black box" 18'which is coupled to vacuum source 12 by vacuum conduit l4, l6 andT-connection 20. A source of electrical energy 22 is shown connected toapparatus 18 to provide power for operating the valve means describedbelow. The receptacle 10 is pro vided with an airtight stopper 24 whichincludes apertures for admitting inlet pipe 26 and outlet pipe 28 intothe airtight enclosure forrned within the receptacle. An inlet device orcatheter 30 is coupled to inlet pipe 26 by a length of flexible conduit32, and outlet pipe 24 is coupled to vacuum conduit 14 directly.

Operation of vacuum pressure source 12 acts to evacuate air from withinreceptacle 10 to create a vacuum which draws fluids through catheter 30,conduit 32 and inlet pipe 26 into the receptacle. Adjustablepressure-control apparatus 18 continuously senses pressure levels withinvacuum conduit 14, 16 and responds to different pressure levels in themanner described below.

FIG. 2 represents a detailed, partial sectional view of the controlapparatus contained with black box 18. This apparatus may be seen tocomprise a pressure transducer 34, an atmospheric vent valve 36, and anelectrically driven motive power source 38 for operating valve 36, and aplunger-actuated electrical switch 40 for controlling operation ofmotive power source 38. In addition, a power switch 42 may be providedas a means to shut off supply of electrical energy to the controlapparatus.

Pressure transducer 34 comprises a housing 44 and a flexible diaphragm46 which together define an enclosed pressure chamber 48. T-connection20 opens into chamber 48 so that the pressure within this chambercorresponds to the pressure in vacuum conduit I4, 16. A compressionspring 50 biases diaphragm 46 upward against a movable elementrepresented by transducer plunger 52, and acts against the oppositeforce which is exerted on the diaphragm by the effect of vacuum pressurewithin chamber 48.

Atmospheric vent valve 36 includes a sliding sealing member 54 whichacts to seal off a vent passage 56 under the normal spring pressure of acompression spring 58. The interior 60 of valve 36 is open to ambientatmosphere conditions through vent apertures 62 which are formed in thebody of the valve. Vent passage 56 may be seen to open into transducerchamber 48 at one end, and into the interior 60 of valve 36, at theother end. Thus, when sliding seal 54 is drawn back against the force ofcompression spring 58, to open the end of vent passage 56, atmosphericor extemal air pressure will be admitted into transducer chamber 48through the valve.

Movement of the sliding seal 54 in valve 36 is controlled byelectrically driven motive power source 38 through a coupling link 64and a rotary eccentric arm 66. Motive source 38, ac-

. cordingly, is preferably a rotary device such as a timer motor orsimilar electrical motor.

When power switch 42 is closed" so as to complete an electrical circuitpath, the supply of electrical energy from source 22 to motor 38 becomessubject to control by plungeractuated switch 40. In this embodiment ofthis invention,

switch 40 is of the normally closed type, i.e. when pressure onswitch-actuating plunger 68 is released, the switch will close" tocomplete an electrical circuit, and conversely, the switch will remainin open condition while pressure on actuating plunger 68 is maintained.

As illustrated in FIG. 2, switch 40 is pivotally mounted about an axis70 which is coupled to a fixed position such as support 72 on transducerhousing 44. A tension spring 74 is coupled to the free end of the switchso as to bias the switch against adjustment rod 76. The adjustment rodis threadly engaged in a threaded aperture 78 and in the wall of box" 18and is provided with a handling knob 18 to facilitate rotation. Thedrawing clearly illustrates the rotation of rod 76 will advance itrelative to the wall of box 18, and will tend to urge switch 40 aroundpivot axis 70 in a clockwise direction and against transducer plunger52.

It may be seen now that the control apparatus which has been described,operates in the following manner: the presence of normal vacuum pressurein chamber 48, as sensed through T-connection 20, will be overcome bythe force of bias spring 50 so as to maintain upward pressure on switchactivator 68 through transducer plunger 52. Switch 40 will be maintainedin open" position under these conditions and motive source 38 willremain inoperative in the position shown. However, an increase in vacuumpressure in chamber 48, such as might be caused by an obstruction offlow through catheter 30, will overcome the force of bias spring 50 topull diaphragm 46 and transducer plunger 52 downward away from switchactuator 68. Upon release of plunger pressure on actuator 68, switch 40will return to closed" position and will thereby initiate operation ofelectrically driven motive source 38. As source 38 rotates from theposition shown, sliding seal 54 of valve 36 will be drawn back againstspring 58 so as to open vent passage 56 to atmospheric pressure. Theresultant presence of atmospheric pressure in chamber 48 of transducer34 will be transmitted through conduit 14 to receptacle 10, and,ultimately the interior of catheter 30. Atmospheric pressure at thispoint will then permit debris and other obstructions to fall away fromthe inlet apertures of catheter 30. The presence of atmospheric pressurein chamber 48 will have the further effect of permitting spring 50 toreturn transducer plunger 52 into operative engagement with switchactuator 68 so as to open switch 40. With switch 40 again in openposition, the electrical supply to motive source 38 will be cut off andthe motor preferably will return to the position shown in FIG. 2 so asto again seal vent passage 56. Electrical motors which return to a givenposition upon interruption of power are generally available. It isobvious that this cycle of opening and closing vent valve 36 willcontinue so long as suction pressure within chamber 48 continues toexceed a preselected maximum value.

Selection of the maximum suction pressure value which will initiate thedescribed venting cycle is accomplished by means of adjustment rod 76.The position of switch 40 relative to transducer plunger 52, asdetermined by rod 76, will determine the length of travel required fortransducer plunger 52 to relieve pressure on switch actuator 68. Sincethe length of travel of plunger 52 against the force of bias spring 50will be proportional to the suction pressure in chamber 48, it is clearthat the position of switch 40 will determine the vacuum pressure withintransducer 34 which is required to permit the switch to close.

FIG. 3 illustrates an alternative embodiment of this invention. The FIG.shows, schematically, a transducer plunger 152, a plunger-actuatedcontrol switch 140, a motive power source 138 for controlling a ventva.lve'(not shown), an electrically powered vacuum pressure source 112and a power switch 142. The operation of this embodiment differs fromthat previously explained, in that plunger-actuated switch 140 is usedhere to control operation of the vacuum pressure source 112 instead ofthe vent valve motive power source 138. To accomplish this end, switch140 is of the normally open type rather than the normally closed typeshown in FIG. 2.

The pressure transducer and vent valve elements of this embodiment (notshown in FIG. 3) may be identical to those illustrated in FIG. 2. Thus,it may be seen that upon the closing of power switch 142 under normalconditions, the vent valve motive source 138 and vacuum pressure source112 will operate continuously. Accordingly, in this embodiment, thevacuum conduit lines (not shown) will be periodically vented toatmospheric pressure on a continuing and repetitive basis during normaloperation. However, in response to the buildup of excess vacuum pressurein the system, withdrawal of the transducer plunger 152 will permitcontrol switch to return to open position. In the open position, switch140 will halt operation of the vacuum pressure source until excessivevacuum in the system is relieved.

This invention has thus been described, but it is desired to beunderstood that is is not confined to the particular forms or usagesshown and described, the same being merely illustrative, and that theinvention may be carried out in other ways without department from thespirit of the invention; therefore, the right is broadly claimed toemploy all equivalent instrumentalities combing with the scope of theappendent claims, and by means of which objects of this invention areattained and new results accomplished, as it is obvious that theparticular embodiments herein shown and described are only some of themany that can be employed to obtain these objects and accomplish theseresults.

I claim:

1. A pressure relieving evacuator system, comprising:

a substantially closed receptacle having an inlet passage and an outletpassage;

a source of vacuum pressure having a vacuum pressure outlet coupled tothe outlet passage of said receptacle and creating vacuum pressuretherein;

a pressure transducer means, including a movable element and a pressurechamber, wherein said movable element is displaced relative to a givenposition in response to variations of pressure within said pressurechamber;

the said pressure chamber having a vacuum pressure inlet coupled to thesaid outlet passage of said receptacle;

controllable air valve means, movable under control between an openposition and a closed position, said air valve means being coupled tosaid pressure chamber for admitting external air pressure into saidchamber when in said open position;

2. The pressure relieving evacuator system of claim 1, wherein saidcontrollable air valve means is electrically controllable, and saidmechanically operated control means comprises a mechanically operatedelectric switch means.

3. The pressure relieving evacuator system of claim 2, wherein saidelectrically controllable air valve means comprises: a body memberhaving an air passage coupled to the interior of said pressure chamber;a sliding seal member coupled to said body member for slidabledisplacement between a first position in which said air passage issealed against the passage of air and a second position in which saidair passages open to external air pressure; and an electric motor devicehaving a driven rotary eccentric member coupled to said sliding sealmember for displacing said seal member between said first and secondpositions.

4. The pressure relieving evacuator system of claim 2, wherein: thetotal movement of said movable element in said pressure transducer isproportional to the variations of pressure within said pressure chamber;and the position of said electrical switch means relative to saidmovable element is adjustable to select the total movement of saidmovable element which will operate said switch means.

5. A pressure relieving evacuator system, in accordance with claim 4,further including: rotatable threaded rod means coupled between saidpressure transducer and said electrical switch means to threadedlyadvance and retract said switch means relative to the said movableelement of said pressure transducer, when said rod is rotated.

6. Tire pressure relieving evacuator system of claim 1, wherein saidpressure transducer means comprises: a body member; a flexible diaphragmelement coupled to said body member and forming a wall of said pressurechamber; and a plunger member, slidably mounted to said body member,having one end coupled to said flexible diaphragm element and anotherend mechanically coupled to said mechanically operated control means,operating said control means in a substantially closed receptacle havingan inlet passage and an outlet passage;

a controllable source of vacuum pressure having a vacuum pressure outletcoupled to the closed receptacle and admitting vacuum pressure into theoutlet passage of said receptacle; v

said controllable source of vacuum pressure being selectivelycontrollable to supply or withhold vacuum pressure;

a pressure transducer means, including a movable element and a pressurechamber, producing movement of said movable element in response tovariations of pressure with said pressure chamber; I

said pressure chamber having a vacuum pressure inlet coupled to the saidoutlet passage of said receptacle;

periodically operating air valve means adapted to move periodicallybetween an open position and a closed position, said air valve meansbeing coupled to said pressure chamber for admitting external airpressure into said chamber when in said open position;

mechanically operated control means mechanically coupled to the saidmovable element of said transducer, and to said controllable source ofvacuum pressure to selectively control said source in response tomovement of said movable element.

8. The pressure relieving evacuator system of claim 7,

wherein:

said controllable source of vacuumpressure comprises an electricallyoperated vacuum pump;

and said mechanically operated control means comprises a mechanicallyoperated electrical switch means electrically connected to start and"stop operation of said vacuum pump upon operation of said switch meansin response to variations of vacuum pressure within said pressurechamber. g

9. In a pressure relieving evacuator system having a substantiallyclosed receptacle which includes an inlet passage and an outlet passage,and a source of vacuum pressure, coupled to provide vacuum pressure inthe outlet passage of said receptacle, control apparatus for relievingvacuum pressure in said receptacle, in response to an increase of saidvacuum pressure in said receptacle in response to an increase of saidvacuum pressure, said control apparatus comprising:

a pressure transducer means including a movable element and a pressurechamber, for producing movement of said movable element in response tovariations of pressure within said pressure chamber;

the said pressure chamber having a vacuum pressure inlet coupled to theoutlet passage of the receptacle;

controllable air valve means, movable under control between an openposition and a closed position, said air valve means being coupled tosaid pressure chamber for admitting external air pressure into saidchamber when in said open position;

and, mechanically operated control means mechanically coupled to thesaid movable element of said transducer means and to said controllableair valve means operating said air valve means between open and closedposition in response to displacement of said movable element.

10. Control apparatus in accordance with claim 9, wherein saidcontrollable air valve means is electrically operated, and saidmechanically operated control means comprises a mechanically operatedelectrical switch means for controlling said air valve means.

1. A pressure relieving evacuator system, comprising: a substantiallyclosed receptacle having an inlet passage and an outlet passage; asource of vacuum pressure having a vacuum pressure outlet coupled to theoutlet passage of said receptacle and creating vacuum pressure therein;a pressure transducer means, including a movable element and a pressurechamber, wherein said movable element is displaced relative to a givenposition in response to variations of pressure within said pressurechamber; the said pressure chamber having a vacuum pressure inletcoupled to the said outlet passage of said receptacle; controllable airvalve means, movable under control between an open position and a closedposition, said air valve means being coupled to said pressure chamberfor admitting external air pressure into said chamber when in said openposition;
 2. The pressure relieving evacuator system of claim 1, whereinsaid controllable air valve means is electrically controllable, and saidmechanically operated control means comprises a mechanically operatedelectric switch means.
 3. The pressure relieving evacuator system ofclaim 2, wherein said electrically controllable air valve meanscomprises: a body member having an air passage coupled to the Interiorof said pressure chamber; a sliding seal member coupled to said bodymember for slidable displacement between a first position in which saidair passage is sealed against the passage of air and a second positionin which said air passages open to external air pressure; and anelectric motor device having a driven rotary eccentric member coupled tosaid sliding seal member for displacing said seal member between saidfirst and second positions.
 4. The pressure relieving evacuator systemof claim 2, wherein: the total movement of said movable element in saidpressure transducer is proportional to the variations of pressure withinsaid pressure chamber; and the position of said electrical switch meansrelative to said movable element is adjustable to select the totalmovement of said movable element which will operate said switch means.5. A pressure relieving evacuator system, in accordance with claim 4,further including: rotatable threaded rod means coupled between saidpressure transducer and said electrical switch means to threadedlyadvance and retract said switch means relative to the said movableelement of said pressure transducer, when said rod is rotated.
 6. Thepressure relieving evacuator system of claim 1, wherein said pressuretransducer means comprises: a body member; a flexible diaphragm elementcoupled to said body member and forming a wall of said pressure chamber;and a plunger member, slidably mounted to said body member, having oneend coupled to said flexible diaphragm element and another endmechanically coupled to said mechanically operated control means,operating said control means in response to displacement of said plungerupon flexure of said diaphragm.
 7. A pressure relieving evacuator systemcomprising: a substantially closed receptacle having an inlet passageand an outlet passage; a controllable source of vacuum pressure having avacuum pressure outlet coupled to the closed receptacle and admittingvacuum pressure into the outlet passage of said receptacle; saidcontrollable source of vacuum pressure being selectively controllable tosupply or withhold vacuum pressure; a pressure transducer means,including a movable element and a pressure chamber, producing movementof said movable element in response to variations of pressure with saidpressure chamber; said pressure chamber having a vacuum pressure inletcoupled to the said outlet passage of said receptacle; periodicallyoperating air valve means adapted to move periodically between an openposition and a closed position, said air valve means being coupled tosaid pressure chamber for admitting external air pressure into saidchamber when in said open position; mechanically operated control meansmechanically coupled to the said movable element of said transducer, andto said controllable source of vacuum pressure to selectively controlsaid source in response to movement of said movable element.
 8. Thepressure relieving evacuator system of claim 7, wherein: saidcontrollable source of vacuum pressure comprises an electricallyoperated vacuum pump; and said mechanically operated control meanscomprises a mechanically operated electrical switch means electricallyconnected to start and stop operation of said vacuum pump upon operationof said switch means in response to variations of vacuum pressure withinsaid pressure chamber.
 9. In a pressure relieving evacuator systemhaving a substantially closed receptacle which includes an inlet passageand an outlet passage, and a source of vacuum pressure coupled toprovide vacuum pressure in the outlet passage of said receptacle,control apparatus for relieving vacuum pressure in said receptacle, inresponse to an increase of said vacuum pressure in said receptacle inresponse to an increase of said vacuum pressure, said control apparatuscomprising: a pressure transducer means including a movable element anda pressure chamber, for producing movement of said movable eleMent inresponse to variations of pressure within said pressure chamber; thesaid pressure chamber having a vacuum pressure inlet coupled to theoutlet passage of the receptacle; controllable air valve means, movableunder control between an open position and a closed position, said airvalve means being coupled to said pressure chamber for admittingexternal air pressure into said chamber when in said open position; and,mechanically operated control means mechanically coupled to the saidmovable element of said transducer means and to said controllable airvalve means operating said air valve means between open and closedposition in response to displacement of said movable element. 10.Control apparatus in accordance with claim 9, wherein said controllableair valve means is electrically operated, and said mechanically operatedcontrol means comprises a mechanically operated electrical switch meansfor controlling said air valve means.